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1.
Female Pelvic Med Reconstr Surg ; 27(1): 39-45, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31008776

RESUMO

OBJECTIVES: To assess impact of a decision aid video in Latina patients with symptomatic pelvic organ prolapse (POP) on knowledge, satisfaction and decisional conflict related to initial treatment selection. METHODS: Pilot study with randomized prospective design. Thirty Latina women with symptomatic POP were randomized to a decision aid intervention plus standard care (N = 15) or standard care alone (N = 15) group. Decision aid intervention consisted of a 10-minute video presented at time of initial evaluation for POP. Outcome measures included the Prolapse and Incontinence Knowledge Quiz ("Knowledge"), the Satisfaction with Decision ("Satisfaction") and Decisional Conflict (DCS) scales, and were assessed at 4 different timepoints: after initial visit, and at 1, 3 and 6 months after. Data was analyzed using repeated-measures ANOVA and pairwise between-group comparisons. RESULTS: Demographic and baseline data were similar between groups. There was a significant interaction between groups and time on the Knowledge scores (P = 0.03). Knowledge scores were higher at the initial visit in the intervention group (10.6 ± 0.8 vs 9.53 ± 1.4, P = 0.014). Satisfaction scores were lower in the intervention group on longitudinal analysis, indicating higher satisfaction (P = 0.02). There was no difference on overall Decisional Conflict scores between groups. The intervention group had lower scores on the "effective decision" DCS subscale at 3 and 6 months and "informed" DCS subscale at 3 months. CONCLUSIONS: A decision aid video intervention in Latina women with POP used at the time of initial evaluation may help the patient make a more informed treatment decision by increasing condition-related knowledge and lead to greater long-term satisfaction.


Assuntos
Tomada de Decisões , Técnicas de Apoio para a Decisão , Prolapso de Órgão Pélvico/terapia , Gravação em Vídeo , Idoso , Feminino , Hispânico ou Latino , Humanos , Pessoa de Meia-Idade , Prolapso de Órgão Pélvico/diagnóstico , Projetos Piloto , Estudos Prospectivos , Autorrelato
2.
Biol Reprod ; 96(1): 81-92, 2017 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-28395337

RESUMO

Although the positive effects of vaginal estrogens and the selective estrogen receptor modulator, ospemifene (OS), on the vaginal epithelium are well recognized, less is known regarding the effects of these therapies on the lower urinary tract or vaginal muscularis. Clinical evidence suggests that vaginally administered estrogen may improve overactive bladder-related symptoms. The objective of this study was to compare the effects of OS, vaginal conjugated equine estrogens (CEE), or both on the vaginal wall and lower urinary tract in a rat model of menopause. Contractile force of the bladder neck, dome, and external urethral sphincter at optimal field stimulation did not differ significantly among treatment groups. Pharmacologic responses to atropine, carbachol, and potassium chloride were similar among groups. Vaginal epithelial thickness and differentiation were differentially regulated by CEE or OS. Ospemifene altered epithelial differentiation pathways in vaginal epithelium in a unique way, and these effects were additive with local CEE. Unless contraindicated, the beneficial effects of vaginal CEE on the vaginal wall outweigh those of OS.


Assuntos
Estrogênios Conjugados (USP)/uso terapêutico , Estrogênios/uso terapêutico , Tamoxifeno/análogos & derivados , Uretra/efeitos dos fármacos , Bexiga Urinária/efeitos dos fármacos , Vagina/efeitos dos fármacos , Administração Intravaginal , Administração Oral , Animais , Avaliação Pré-Clínica de Medicamentos , Estrogênios/farmacologia , Estrogênios Conjugados (USP)/farmacologia , Feminino , Menopausa , Distribuição Aleatória , Ratos Sprague-Dawley , Tamoxifeno/farmacologia , Tamoxifeno/uso terapêutico
4.
Exp Mol Pathol ; 99(3): 702-6, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26546836

RESUMO

BACKGROUND: Human papillomavirus (HPV) is a highly prevalent sexually transmitted virus causing cytological alterations that precede cervical cancer. Approximately 130 genotypes have been sequenced. Low-grade squamous intraepithelial lesions (LSIL) are the most frequent cytological alteration and have an uncertain behavior. OBJECTIVES: To analyze the frequency of HPV types in LSIL and their association with the regression, persistence or progression of these lesions. METHODS: A cohort study of forty patients with LSIL cytology was conducted from December 2007 to March 2011. The follow-up lasted two years and included cytology and colposcopy. HPV detection was performed using PCR, and genotyping was performed using PCR-specific and RFLP techniques. RESULTS: DNA-HPV was detected in 87% (35/40) of the cases, with oncogenic HPV accounting for 76%; type 16 in 32% (11/35) and type 18 in 20%. LSIL regression, persistence and progression rates at the end of the study were 60%, 23% and 17%, respectively. There was 50% regression in lesions in the high oncogenic risk group (types 16 and 18). CONCLUSION: HPV 16 was the most frequent genotype found in LSIL. The persistence and progression of the LSIL were related to the persistence of oncogenic HPV. The longer the follow-up time, the lower the LSIL persistence rate and the higher its regression rate; the progression rate remained stable. In addition to the presence of oncogenic HPV, other factors are necessary for the progression of LSIL.


Assuntos
Infecções por Papillomavirus/virologia , Lesões Intraepiteliais Escamosas Cervicais/patologia , Lesões Intraepiteliais Escamosas Cervicais/virologia , Progressão da Doença , Feminino , Genótipo , Humanos , Papillomaviridae/genética , Infecções por Papillomavirus/complicações , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição
5.
J Mal Vasc ; 40(1): 10-7, 2015 Feb.
Artigo em Francês | MEDLINE | ID: mdl-25631643

RESUMO

AIM: Masked hypertension (MH) is defined by a normal office blood pressure (BP) and a high ambulatory BP. MH is characterized by high prevalence and poor cardiovascular prognosis. The aim of this study was to evaluate the usefulness of routine MH screening, using 24-h blood pressure monitoring (BPM), among patients with peripheral arterial disease (PAD). METHODS: Between 2011 and 2013, 54 patients with PAD were included in the Hypertension and Vascular Medicine Unit of the Lille Hospital. They had normal office BP (< 140/90mmHg). A 24 h-BPM device was set on each patient. MH diagnosis was established if the BP average over 24 hours was ≥ 130/80 mmHg and/or the daytime average ≥ 135/85 mmHg and/or the nighttime average ≥ 120/70 mmHg. RESULTS: MH prevalence was about 42.6% (23 patients). It was significantly more frequent in diabetic patients (odds ratio: 3.8 [1.1-12.8]), in patients with known hypertension (odds ratio: 5 [1.5-16.9]) or with high normal office BP (<140/90 mmHg but ≥ 130/85 mmHg) (odds ratio: 5.6 [1.7-18.2]). By multivariate analysis, only known hypertension and high normal office BP were associated with masked hypertension. CONCLUSION: The high prevalence of MH in patients with PAD shows us the importance of a careful screening of MH in this population, especially in diabetic patients, in patients with known hypertension or with a high normal office BP.


Assuntos
Hipertensão Mascarada/diagnóstico , Doença Arterial Periférica/complicações , Doença Arterial Periférica/fisiopatologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Pressão Sanguínea , Monitorização Ambulatorial da Pressão Arterial , Complicações do Diabetes/epidemiologia , Diabetes Mellitus/fisiopatologia , Feminino , França/epidemiologia , Humanos , Masculino , Hipertensão Mascarada/epidemiologia , Programas de Rastreamento , Pessoa de Meia-Idade , Razão de Chances , Projetos Piloto
6.
Biol Reprod ; 92(2): 43, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25537371

RESUMO

The objective of this study was to compare the effects of systemic and local estrogen treatment on collagen assembly and biomechanical properties of the vaginal wall. Ovariectomized nulliparous rats were treated with estradiol or conjugated equine estrogens (CEEs) either systemically, vaginal CEE, or vaginal placebo cream for 4 wk. Low-dose local CEE treatment resulted in increased vaginal epithelial thickness and significant vaginal growth without uterine hyperplasia. Furthermore, vaginal wall distensibility increased without compromise of maximal force at failure. Systemic estradiol resulted in modest increases in collagen type I with no change in collagen type III mRNA. Low-dose vaginal treatment, however, resulted in dramatic increases in both collagen subtypes whereas moderate and high dose local therapies were less effective. Consistent with the mRNA results, low-dose vaginal estrogen resulted in increased total and cross-linked collagen content. The inverse relationship between vaginal dose and collagen expression may be explained in part by progressive downregulation of estrogen receptor-alpha mRNA with increasing estrogen dose. We conclude that, in this menopausal rat model, local estrogen treatment increased total and cross-linked collagen content and markedly stimulated collagen mRNA expression in an inverse dose-effect relationship. High-dose vaginal estrogen resulted in downregulation of estrogen receptor-alpha and loss of estrogen-induced increases in vaginal collagen. These results may have important clinical implications regarding the use of local vaginal estrogen therapy and its role as an adjunctive treatment in women with loss of vaginal support.


Assuntos
Colágeno/metabolismo , Estradiol/administração & dosagem , Estrogênios Conjugados (USP)/administração & dosagem , Vagina/efeitos dos fármacos , Administração Intravaginal , Administração Oral , Animais , Fenômenos Biomecânicos/efeitos dos fármacos , Feminino , Ratos , Útero/efeitos dos fármacos , Útero/metabolismo , Vagina/metabolismo , Cremes, Espumas e Géis Vaginais
7.
Eur J Cancer ; 50(16): 2846-54, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25155250

RESUMO

AIM: This work describes the human papillomavirus (HPV) prevalence and the HPV type distribution in a large series of vaginal intraepithelial neoplasia (VAIN) grades 2/3 and vaginal cancer worldwide. METHODS: We analysed 189 VAIN 2/3 and 408 invasive vaginal cancer cases collected from 31 countries from 1986 to 2011. After histopathological evaluation of sectioned formalin-fixed paraffin-embedded samples, HPV DNA detection and typing was performed using the SPF-10/DNA enzyme immunoassay (DEIA)/LiPA25 system (version 1). A subset of 146 vaginal cancers was tested for p16(INK4a) expression, a cellular surrogate marker for HPV transformation. Prevalence ratios were estimated using multivariate Poisson regression with robust variance. RESULTS: HPV DNA was detected in 74% (95% confidence interval (CI): 70-78%) of invasive cancers and in 96% (95% CI: 92-98%) of VAIN 2/3. Among cancers, the highest detection rates were observed in warty-basaloid subtype of squamous cell carcinomas, and in younger ages. Concerning the type-specific distribution, HPV16 was the most frequently type detected in both precancerous and cancerous lesions (59%). p16(INK4a) overexpression was found in 87% of HPV DNA positive vaginal cancer cases. CONCLUSIONS: HPV was identified in a large proportion of invasive vaginal cancers and in almost all VAIN 2/3. HPV16 was the most common type detected. A large impact in the reduction of the burden of vaginal neoplastic lesions is expected among vaccinated cohorts.


Assuntos
Carcinoma de Células Escamosas/virologia , Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/virologia , Neoplasias Vaginais/virologia , Idoso , Carcinoma de Células Escamosas/complicações , Carcinoma de Células Escamosas/epidemiologia , Estudos Transversais , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , DNA Viral/análise , Feminino , Papillomavirus Humano 16/isolamento & purificação , Humanos , Técnicas Imunoenzimáticas , Cooperação Internacional , Pessoa de Meia-Idade , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/epidemiologia , Distribuição de Poisson , Lesões Pré-Cancerosas/epidemiologia , Lesões Pré-Cancerosas/virologia , Prevalência , Análise de Regressão , Estudos Retrospectivos , Resultado do Tratamento , Neoplasias Vaginais/complicações , Neoplasias Vaginais/epidemiologia
8.
Neuroscience ; 272: 188-98, 2014 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-24814729

RESUMO

Glutamate-induced excitotoxicity involves a state of acute oxidative stress, which is a crucial event during neuronal degeneration and is part of the physiopathology of neurodegenerative diseases. In this work, we evaluated the ability of sulforaphane (SULF), a natural dietary isothiocyanate, to induce the activation of transcription factor Nrf2 (a master regulator of redox state in the cell) in a model of striatal degeneration in rats infused with quinolinic acid (QUIN). Male Wistar rats received SULF (5mg/kg, i.p.) 24h and 5min before the intrastriatal infusion of QUIN. SULF increased the reduced glutathione (GSH) levels 4h after QUIN infusion, which was associated with its ability to increase the activity of glutathione reductase (GR), an antioxidant enzyme capable to regenerate GSH levels at 24h. Moreover, SULF treatment increased glutathione peroxidase (GPx) activity, while no changes were observed in γ-glutamyl cysteine ligase (GCL) activity. SULF treatment also prevented QUIN-induced oxidative stress (measured by oxidized proteins levels), the histological damage and the circling behavior. These results suggest that the protective effect of SULF could be related to its ability to preserve GSH levels and increase GPx and GR activities.


Assuntos
Anticarcinógenos/farmacologia , Glutationa/metabolismo , Isotiocianatos/farmacologia , Ácido Quinolínico/metabolismo , Animais , Glutationa Redutase/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Doenças Neurodegenerativas/metabolismo , Ratos Wistar , Sulfóxidos
9.
Neuroscience ; 252: 384-95, 2013 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-23988432

RESUMO

The aim of this study was to analyze the effects of chronic oxidative stress on mitochondrial function and its relationship to progressive neurodegeneration in the hippocampus of rats chronically exposed to ozone. Animals were exposed to 0.25 ppm ozone for 7, 15, 30, or 60 days. Each group was tested for (1) protein oxidation and, manganese superoxide dismutase (Mn-SOD), glutathione peroxidase (GPx) and succinate dehydrogenase (SDH) activity using spectrophotometric techniques, (2) oxygen consumption, (3) cytochrome c, inducible nitric oxide synthase (iNOS), peroxisome proliferator-activated receptor γ Co-activator 1α (PGC-1α), B-cell lymphoma (Bcl-2), and Bax expression using Western blotting, (4) histology using hematoxylin and eosin staining, and (5) mitochondrial structure using electron microscopy. Our results showed increased levels of carbonyl protein and Mn-SOD activity after 30 days of ozone exposure and decreased GPx activity. The SDH activity decreased from 7 to 60 days of exposure. The oxygen consumption decreased at 60 days. Western blotting showed an increase in cytochrome c at 60 days of ozone exposure and an increase in iNOS up to 60 days of ozone exposure. The expression of PGC-1α was decreased after 15, 30, and 60 days compared to the earlier time Bcl-2 was increased at 60 days compared to earlier time points, and Bax was increased after 30 and 60 days of exposure compared to earlier time points. We observed cellular damage, and mitochondrial swelling with a loss of mitochondrial cristae after 60 days of exposure. These changes suggest that low doses of ozone caused mitochondrial abnormalities that may lead to cell damage.


Assuntos
Hipocampo/metabolismo , Hipocampo/patologia , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Estresse Oxidativo/fisiologia , Animais , Western Blotting , Imuno-Histoquímica , Oxidantes Fotoquímicos/toxicidade , Ozônio/toxicidade , Ratos , Ratos Wistar
12.
Brain Res ; 1388: 134-40, 2011 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-21300037

RESUMO

Brain damage from neonatal hypoxia-ischemia (HI) plays a major role in neonatal mortality and morbidity. Using the Rice-Vannucci model of HI in rats, we verified that 8 days after HI injury, adenosine deaminase (ADA), N-acetyl-glucosaminidase (NAG) and myeloperoxidase (MPO) activities increased in the left hemisphere hippocampus (HI group); however, the activity of 5'-nucleotidase (5'NT) remained unchanged. In the hematoxylin-eosin analysis (HE), we detected selective and delayed degeneration of hippocampal pyramidal neurons and astroglial reaction accompanied by glial fibrillary acidic protein (GFAP)-positive and vimentin-positive in the immunohistochemistry analysis in the HI group compared with the control group. We observed the selective necrosis of neurons, vascular endothelial proliferation and inflammatory response accompanied by the increase of the key enzyme of adenosine metabolism in the HI group. The increase of ADA activity, despite the 5'NT activity was not altered, indicates the predominance of ADA activity in the postischemic homeostasis of extra cellular adenosine. The presence of leukocytes into the ischemic areas displays the possible importance of the neutrophil-macrophages associated with the increase of MPO and NAG activities 8 days after HI. These findings may contribute to the evaluation of some consequences of the damage caused by neonatal HI.


Assuntos
Hipocampo/enzimologia , Hipocampo/patologia , Hipóxia-Isquemia Encefálica/metabolismo , Hipóxia-Isquemia Encefálica/patologia , Animais , Animais Recém-Nascidos , Astrócitos/metabolismo , Astrócitos/patologia , Hexosaminidases/metabolismo , Hipocampo/lesões , Hipóxia-Isquemia Encefálica/imunologia , Imuno-Histoquímica , Inflamação/metabolismo , Inflamação/patologia , Masculino , Neurônios/metabolismo , Neurônios/patologia , Peroxidase/metabolismo , Ratos , Ratos Wistar
13.
J Phys Chem A ; 114(4): 1953-6, 2010 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-20055398

RESUMO

The ground state and the LS terms coming from the ground-state configuration, [Ar]-3d(6)4s(2), of the iron atom are studied by carrying out an all electron Variational Monte Carlo calculation. Explicitly correlated trial functions including near degeneracy effects are used. The effect of electronic correlations and the importance of near degeneracy effects are systematically analyzed for the states here considered and compared with the experimental values. Correlations are important to reproduce, even qualitatively, the low-lying spectrum of this atom. A significant quantitative improvement when comparing with the experimental values is achieved when near degeneracy is considered along with dynamic correlations in the variational trial wave function. Finally, the effect of relativity on the results here reported is discussed.

14.
Inhal Toxicol ; 21(11): 906-12, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19459774

RESUMO

Cigarette smoke is a complex mixture of various toxic substances that are capable of initiating oxidative damage and promoting blood platelet alterations. In this study, we investigated the activities of the ectoenzymes NTPDase (ectonucleoside triphosphate diphosphohydrolase, CD39) and 5'-nucleotidase (CD73) in platelets as well as adenosine deaminase (ADA) in the plasma of rats exposed to aged and diluted sidestream smoke during 4 weeks. The rats were divided into two groups: I (control) and II (exposed to smoke). After the exposure period, blood was collected and the platelets and plasma were separated for enzymatic assay. The results demonstrated that NTPDase (with ATP as substrate) and 5'-nucleotidase (AMP as substrate) activities were significantly higher in group II (p < 0.05) as compared to group I, while no significant difference was observed for NTPDase with ADP as substrate. The ADA activity was significantly reduced in group II (p < 0.05) as compared with group I. Platelet aggregation was significantly increased in group II (p < 0.05) as compared with group I. We suggest that these alterations in the activity of enzymes from the purinergic system are associated with an increase in platelet aggregation. However, our study has demonstrated that the organism tries to compensate for this enhanced aggregation by increasing hydrolysis of AMP and reducing hydrolysis of adenosine, a potent inhibitor of aggregation and an important modulator of vascular tone.


Assuntos
Adenosina Desaminase/metabolismo , Adenosina Trifosfatases/metabolismo , Poluição por Fumaça de Tabaco/efeitos adversos , 5'-Nucleotidase/sangue , Adenosina/sangue , Animais , Gasometria , Plaquetas/enzimologia , Carboxihemoglobina/metabolismo , Concentração de Íons de Hidrogênio , Pulmão/enzimologia , Pulmão/patologia , Masculino , Agregação Plaquetária/efeitos dos fármacos , Fibrose Pulmonar/induzido quimicamente , Fibrose Pulmonar/patologia , Ratos , Ratos Wistar , Nicotiana/química
15.
Free Radic Biol Med ; 29(7): 602-11, 2000 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-11033412

RESUMO

Reactive oxygen species are involved in gentamicin (GM) nephrotoxicity, and garlic is effective in preventing or ameliorating oxidative stress. Therefore, the effect of garlic on GM nephrotoxicity was investigated in this work. Four groups of rats were studied: (i) fed normal diet (CT), (ii) treated with GM (GM), (iii) fed 2% garlic diet (GA), and (iv) treated with GM and 2% garlic diet (GM + GA). Rats were placed in metabolic cages and GM nephrotoxicity was induced by injections of GM (75 mg/kg every 12 h) for 6 d. Lipoperoxidation and enzyme determinations were made in renal cortex on day 7. GM nephrotoxicity was made evident on day 7 by (i) tubular histological damage, (ii) enhanced BUN and urinary excretion of N-acetyl-beta-D-glucosaminidase, and (iii) decreased creatinine clearance. These alterations were prevented or ameliorated in GM + GA group. The rise in lipoperoxidation and the decrease in Mn-SOD and glutathione peroxidase (GPx) activities observed in the GM group, were prevented in the GM + GA group. Cu, Zn-SOD activity and Mn-SOD and Cu,Zn-SOD content did not change. CAT activity and content decreased in the GM, GA, and GM + GA groups. CAT mRNA levels decreased in the GM group. The protective effect of garlic is associated with the prevention of the decrease of Mn-SOD and GPx activities and with the rise of lipoperoxidation in renal cortex.


Assuntos
Catalase/metabolismo , Alho , Gentamicinas/toxicidade , Glutationa Peroxidase/metabolismo , Rim/efeitos dos fármacos , Rim/enzimologia , Peroxidação de Lipídeos/efeitos dos fármacos , Plantas Medicinais , Superóxido Dismutase/genética , Acetilglucosaminidase/urina , Animais , Nitrogênio da Ureia Sanguínea , Catalase/genética , Dieta , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Rim/patologia , Córtex Renal/efeitos dos fármacos , Córtex Renal/patologia , Masculino , Estresse Oxidativo , Proteinúria , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Superóxido Dismutase/metabolismo
16.
Brain Res ; 858(2): 436-9, 2000 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-10708698

RESUMO

The response of endogenous antioxidants to the N-methyl-D-aspartate (NMDA) receptor agonist and excitotoxin, quinolinic acid (QUIN), was investigated in rat corpus striatum. Animals treated with QUIN (240 nmol/microl), were sacrificed at 120 min after a single intrastriatal injection to examine the alterations in the levels of both reduced (GSH) and oxidized (GSSG) glutathione, and the activities of the antioxidant enzymes, superoxide dismutase (SOD) and glutathione peroxidase (Gpx). Changes in the rate of lipid peroxidation (LP) were also measured after exposure to different doses of QUIN (60, 120, 240 and 480 nmol/microl) as an index of oxidative stress. When compared to control, lipid peroxidation was increased at QUIN doses of 240 and 480 nmol/microl. Striatal levels of GSH and GSSG were decreased and increased, respectively, after QUIN injection; whereas GPx activity was unchanged. Cytosolic copper/zinc SOD (CuZn-SOD) activity decreased after treatment, while mitochondrial manganese SOD (Mn-SOD) was unchanged. The alterations observed on these antioxidant systems suggest that QUIN toxicity is mediated by specific mechanisms leading to oxidative stress.


Assuntos
Antioxidantes/metabolismo , Corpo Estriado/efeitos dos fármacos , Corpo Estriado/enzimologia , Ácido Quinolínico/farmacologia , Animais , Glutationa/metabolismo , Dissulfeto de Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Masculino , Ratos , Ratos Wistar , Superóxido Dismutase/metabolismo
17.
J Membr Biol ; 106(3): 203-10, 1988 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2854164

RESUMO

The epidermal growth factor (EGF) and the platelet-derived growth factor (PDGF) inhibit gap junctional communication in the mammalian cell lines NRK and BalbC 3T3: cell-to-cell transfer of a 400-dalton tracer molecule is reduced and junctional conductance is reduced. The inhibition of cell-to-cell transfer is reversible and dose dependent; half-maximal effects are obtained at 10(-9) and 10(-11) M concentrations of EGF and PDGF, respectively. The response of junctional conductance is detectable within 2 min of EGF application and reaches a maximum within 10 min. It is among the earliest cellular responses to this growth factor and may be significant in the regulation of growth. The response is lacking in EGF receptor-deficient NIH 3T3 cells. The transforming factor beta (TGF beta) enhances junctional communication in BalbC 3T3: cell-to-cell transfer is increased over a period of 8 hr. But in NRK cells, where it upregulates EGF receptors, TGF beta reduces junctional communication synergistically with EGF.


Assuntos
Comunicação Celular , Substâncias de Crescimento/fisiologia , Junções Intercelulares/fisiologia , Animais , Permeabilidade da Membrana Celular , Células Cultivadas , Receptores ErbB/fisiologia , Camundongos , Microeletrodos , Fator de Crescimento Derivado de Plaquetas , Ratos , Receptores de Superfície Celular/fisiologia , Receptores do Fator de Crescimento Derivado de Plaquetas , Fatores de Crescimento Transformadores/fisiologia
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